@danielgreene
Best wishes for a happy ending. :) I have one more suggestion and that is if you are using IE you will find there are many bloggers reporting issues with it. When they switch to Firefox their issues are sometimes solved so you may want to try Firefox.http://www.mozilla.com/en-US/firefox/all.html

@timethief Yes, I tried it with the latest version of Firefox for Mac. I also tried it with the latest versions of Chrome and Opera for Mac. I have emptied the cache. In other words, "I did try the link for browser issues but still have the issue." ;-/

I think what I'm having is what @kansir reported that he got as a response from WordPress: "We've learned that the issue appears only for blogs that use a domain mapping. We do not yet have a solution for the issue but will be working on one."

I still like the P2 theme because it shows the authors and it shows more blog posts per page, but it's too bad the main point of it--dynamic posting from the home page--is not working.

What can I say? The problems are widespread an Staff is aware of them. As an act of desperation you could try switching to the Prologue theme and see if it works for you. Both themes do work for me. I'm on a PC with XP and Firefox 3.6.16.